Nicolás Prados

Monozygotic twinning after assisted reproductive technologies: a case report of asymmetric development and incidence during 19 years in an international group of in vitro fertilization clinics

OBJECTIVE To describe a case of monozygotic twinning with asymmetric development following a single fresh embryo transfer as part of an intracytoplasmic sperm injection (ICSI) treatment. Secondarily, to report the incidence of monozygotic twinning at the IVI (Instituto Valenciano de Infertilidad) clinics. DESIGN Case report. SETTING Private fertility centers. PATIENT(S) A 33-year-old woman with a 2-year history of primary infertility. INTERVENTION(S) Controlled ovarian hyperstimulation and ICSI treatment with single-embryo transfer. MAIN OUTCOME MEASURE(S) Incidence of monozygotic twinning at the IVI clinics. RESULT(S) We report a twin pregnancy after a single-embryo transfer. Twins were dichorionic and diamniotic. One fetus had a 6-day delay in its growth compared with the other when observed by ultrasound. Two female infants were delivered, and despite presenting congenital diseases, they were successfully treated and evolved correctly. A subsequent DNA analysis confirmed that the infants were monozygotic. Furthermore, we estimated a monozygotic twinning rate of 1.17% at the IVI clinics, taking into account those cases in which two or more embryos with heart beats were observed by ultrasound scanning after single-embryo transfers. CONCLUSION(S) Ultrasound scans performed during pregnancy suggested a possible dizygotic origin of the twins, but DNA analysis performed after birth established that they were monozygotic. Genetic analysis is the only valid tool to confirm if like-sex dichorionic twins are monozygotic or dizygotic.

Influence of follicle rupture and uterine contractions on intrauterine insemination outcome: a new predictive model

OBJECTIVE To correlate the detection of follicle rupture and the number of uterine contractions per minute with the outcome of IUI and to build a predictive model for the outcome of IUI including these parameters. DESIGN Retrospective cohort study. SETTING Fertility clinic. PATIENT(S) We analyzed data from 610 women who underwent homologous or donor double IUI from 2005 to 2010 and whose data of uterine contractions or follicle rupture were recorded. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Live-birth rate. RESULT(S) Nine hundred seventy-nine IUI cycles were included. The detection of follicle rupture (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.30-3.01) and the number of uterine contractions per minute (OR, 1.67; 95% CI, 1.02-2.74) assessed after the second insemination procedure of a double IUI were positively correlated with the live-birth rate. A multiple logistic regression model showed that sperm origin, maternal age, follicle count at hCG administration day, follicle rupture, and the number of uterine contractions observed after the second insemination procedure were significantly associated with the live-birth rate. CONCLUSION(S) Follicle rupture and uterine contractions are associated with the success of an IUI cycle. This may open new possibilities to improve the methodology of IUI.

Expression of Tachykinins and Tachykinin Receptors and Interaction with Kisspeptin in Human Granulosa and Cumulus Cells

ABSTRACT The neurokinin B/NK3 receptor (NK3R) and kisspeptin/kisspeptin receptor (KISS1R), two systems which are essential for reproduction, are coexpressed in human mural granulosa (MGC) and cumulus cells (CCs). However, little is known about the presence of other members of the tachykinin family in the human ovary. In the present study, we analyzed the expression of substance P (SP), hemokinin-1 (HK-1), NK1 receptor (NK1R), and NK2 receptor (NK2R) in MGCs and CCs collected from preovulatory follicles of oocyte donors at the time of oocyte retrieval. RT-PCR, quantitative RT-PCR, immunocytochemistry, and Western blotting were used to investigate the patterns of expression of tachykinin and tachykinin receptor mRNAs and proteins and the possible interaction between the tachykinin family and kisspeptin. Intracellular free Ca2+ levels ([Ca2+]i) in MGCs after exposure to SP or kisspeptin in the presence of SP were also measured. We found that SP, HK-1, the truncated NK1R isoform NK1R-Tr, and NK2R were all expressed in MGCs and CCs. NK1R-Tr mRNA and NK2R mRNA and protein levels were higher in MGCs than in CCs from the same patients. Treatment of cells with kisspeptin modulated the expression of HK-1, NK3R, and KISS1R mRNAs, whereas treatment with SP regulated kisspeptin mRNA levels and reduced the [Ca2+]i response produced by kisspeptin. These data demonstrate that the whole tachykinin system is expressed and acts in coordination with kisspeptin to regulate granulosa cell function in the human ovary.

Inter-laboratory agreement on embryo classification and clinical decision: Conventional morphological assessment vs. time lapse

The aim of this study is to determine inter-laboratory variability on embryo assessment using time-lapse platform and conventional morphological assessment. This study compares the data obtained from a pilot study of external quality control (EQC) of time lapse, performed in 2014, with the classical EQC of the Spanish Society for the Study of Reproductive Biology (ASEBIR) performed in 2013 and 2014. In total, 24 laboratories (8 using EmbryoScope™, 15 using Primo Vision™ and one with both platforms) took part in the pilot study. The clinics that used EmbryoScope™ analysed 31 embryos and those using Primo Vision™ analysed 35. The classical EQC was implemented by 39 clinics, based on an analysis of 25 embryos per year. Both groups were required to evaluate various qualitative morphological variables (cell fragmentation, the presence of vacuoles, blastomere asymmetry and multinucleation), to classify the embryos in accordance with ASEBIR criteria and to stipulate the clinical decision taken. In the EQC time-lapse pilot study, the groups were asked to determine, as well as the above characteristics, the embryo development times, the number, opposition and size of pronuclei, the direct division of 1 into 3 cells and/or of 3 into 5 cells and false divisions. The degree of agreement was determined by calculating the intra-class correlation coefficients and the coefficient of variation for the quantitative variables and the Gwet index for the qualitative variables. For both EmbryoScope™ and Primo Vision™, two periods of greater inter-laboratory variability were observed in the times of embryo development events. One peak of variability was recorded among the laboratories addressing the first embryo events (extrusion of the second polar body and the appearance of pronuclei); the second peak took place between the times corresponding to the 8-cell and morula stages. In most of the qualitative variables analysed regarding embryo development, there was almost-perfect inter-laboratory agreement among conventional morphological assessment (CMA), EmbryoScope™ and Primo Vision™, except for false divisions, vacuoles and asymmetry (users of all methods) and multinucleation (users of Primo Vision™), where the degree of agreement was lower. The inter-laboratory agreement on embryo classification according to the ASEBIR criteria was moderate-substantial (Gwet 0.41–0.80) for the laboratories using CMA and EmbryoScope™, and fair-moderate (Gwet 0.21–0.60) for those using Primo Vision™. The inter-laboratory agreement for clinical decision was moderate (Gwet 0.41–0.60) on day 5 for CMA users and almost perfect (Gwet 0.81–1) for time-lapse users. In conclusion, time-lapse technology does not improve inter-laboratory agreement on embryo classification or the analysis of each morphological variable. Moreover, depending on the time-lapse platform used, inter-laboratory agreement may be lower than that obtained by CMA. However, inter-laboratory agreement on clinical decisions is improved with the use of time lapse, regardless of the platform used.

Elective single versus double embryo transfer: live birth outcome and patient acceptance in a prospective randomised trial*

The purpose of this study was to determine which strategy of embryo transfer has a better trade-off in live birth delivery rate versus multiple pregnancy considering patient acceptance: elective single embryo transfer (eSET) or elective double embryo transfer (eDET). In all, 199 women <38 years of age undergoing their first IVF treatment in a private centre were included in a prospective open-label randomised controlled trial. Patients were randomised into four groups: (1) eSET on Day 3; (2) eSET on Day 5; (3) eDET on Day 3; and (4) eDET on Day 5. Per patient, main analysis included acceptance of assigned group, as well as multiple and live birth delivery rates of the fresh cycle. Secondary analysis included the rates of subsequent cryotransfers and the theoretical cumulative success rate. Of 98 patients selected for eSET, 40% refused and preferred eDET. The live birth delivery rate after eDET was significantly higher after eDET versus eSET (65% vs 42%, respectively; odds ratio=1.6, 95% confidence interval 1.1-2.1). No multiple births were observed after eSET, compared with 35% after eDET. Although live birth delivery is higher with eDET, the increased risk of multiple births is avoided with eSET. Nearly half the patients refused eSET even after having been well informed about its benefits.

The Metabolomic Profile of Spent Culture Media from Day-3 Human Embryos Cultured under Low Oxygen Tension

Despite efforts made to improve the in vitro embryo culture conditions used during assisted reproduction procedures, human embryos must adapt to different in vitro oxygen concentrations and the new metabolic milieu provided by the diverse culture media used for such protocols. It has been shown that the embryo culture environment can affect not only cellular metabolism, but also gene expression in different species of mammalian embryos. Therefore we wanted to compare the metabolic footprint left by human cleavage-stage embryos under two types of oxygen atmospheric culture conditions (6% and 20% O2). The spent culture media from 39 transferred and implanted embryos from a total of 22 patients undergoing egg donation treatment was analyzed; 23 embryos came from 13 patients in the 6% oxygen concentration group, and 16 embryos from 9 patients were used in the 20% oxygen concentration group. The multivariate statistics we used in our analysis showed that human cleavage-stage embryos grown under both types of oxygen concentration left a similar metabolic fingerprint. We failed to observe any change in the net depletion or release of relevant analytes, such as glucose and especially fatty acids, by human cleavage-stage embryos under either type of culture condition. Therefore it seems that low oxygen tension during embryo culture does not alter the global metabolism of human cleavage-stage embryos.